Impossible to cancel my contract

I have been trying to cancel my MTN contract on my cell *** which expired on 2015.05.15 since last month. I have send 5 emails to them with no response .I even visited the shop in 3 Rivers to cancel it there, where i was informed that i must phone 808 from my phone.When phoning 808 no operator answers and when someone eventually does i`m am cut off as soon as i try to speak.So MTN how do you expect me to give notice to cancel my contract?`I `m fed up with MTN i have had only GPRS reception were i`m staying and have waited for this 2 years to pass to cancel because i cant even use Facebook or internet on this contract. MTN your service is really very bad! All I want is conformation that my contract is cancelled and no more subtraction of installments after 2015.05.30 because i don't want your contracts!!! My email is [Email Removed]